在Bash脚本中,可以使用if、elif和else语句实现多项选择。这些条件语句可根据条件的结果执行不同的代码块。 if语句用于执行单一条件判断,语法如下: 代码语言:txt 复制 if [ condition ]; then # code block executed when the condition is true fi elif语句用于执行多个条件判断,
echo "Number $n is equal to 150" fi 脚本执行后,输出如下: if-statement-bash-scripting-example Nested if Statement If 语句和 else 语句可以嵌套在 bash 脚本中。关键字 fi 显示了内部 if 语句的结束,所有 if 语句都应该以关键字 fi 结束。 Syntax : if [ condition_command ] then command1 command2...
/bin/bashreadareadbif[$a==$b]thenecho"a和b相等"fiif else语句如果有两个分支，就可以使用 if ...
'Else if'in bash scripting, often written as'elif', is used to check multiple conditions in your code. It is used with the syntax,if [firstStatement]; then... elif [secondCondition]; then... else. It’s a powerful tool that allows your scripts to make decisions based on various scen...
An alternative to if-else statements in shell scripting is the case statement. The case statement allows you to match a value against multiple patterns and execute different blocks of code based on the match. Here’s an example: case$varin1)echo"Variable is 1.";;2)echo"Variable is 2."...
Scripting 1. Introduction As the ubiquitous Linux shell,Bashhas its own features and scripting syntax, which upgrade those of the regularshshell. On the other hand, most shells agree on how the basicconditional expressionswork at the logical and syntactic levels. ...
关于bash中if语法结构的广泛误解 Linux 技巧:Bash的测试和比较函数(探密test,[,[[,((和if-then-else) if语法[Linux(bash_shell)] http://blog.csdn.net/ycl810921/article/details/4988778 1: 定义变量时, =号的两边不可以留空格. eg: gender=femal---right gender =femal-...
Linux Shell Scripting If...Else Bash If...Else Statement 常见问题及解决方法 问题:if语句中的条件判断不生效 原因: 条件表达式写错。 条件表达式中使用了错误的比较运算符。 条件表达式中引用的变量未定义或为空。 解决方法: 检查条件表达式的语法和逻辑是否正确。
else # Code block executed when condition is false fi Conditions of using if statement Bash provides several conditionals that you can use within if statements: 1. Numeric Comparisons: -eq: Equal to -ne: Not equal to -gt: Greater than ...
The previous section introduced the concept that there are several reserved words and a number of characters that have an effect on the operation of Bash. The most basic, and probably most widely used conditional logic is with if and else statements. Let's use an example code snippet:...